Use json-bigint to handle correctly numbers too large for Javascript Number such as the values of the fields *l and _version\. By default json-bigint library is not used because the performance difference compared to the native JSON library is too important with "large" chunk of JSON (https://github.com/lbdremy/solr-node-client/issues/114#issuecomment-54165595), but you want to enable it if you use the Optimistic Concurreny feature available in Solr 4.x, along with RealTime Get and Atomic Updates features because they use the _version_ field. In order to enable it do var client = solr.createClient({ bigint : true}) or directly on the client instance client.options.bigint = true.

Migration between 0.2.x and 0.3.x

The only breaking change introduced in v0.3.0 is about method chaining of the solr Client.
Method chaining as simply been removed because we were actually hidding something really interesting and useful
the http.ClientRequest instance.

Migration between 0.3.x and 0.4.x

The only breaking change introduced in 0.4.x is about JSON serialization/deserialization of numbers too large for Javascript Number type. If you were using the Optimistic Concurreny feature available in Solr 4.x, along with RealTime Get and Atomic Updates features which use the _version_ field or *_l type fields you are affected about this change otherwise you are just fine.

If you affected in order to fix that just initialize your client with the bigint flag set to true:

var client = solr.createClient({ bigint :true });

or directly on the Client instance:

client.options.bigint =true;

Post an issue if you have troubles migrating to v0.4.0.

Migration between 0.4.x and 0.5.x

The only breaking change introduced in 0.5.x is introduced in this commit 3cbc7fc6cf631f019a4626913c0a4b616092133b which remove escaping of the Solr special characters in some of the methods of the Query class i.e in Query#rangeFilter, Query#matchFilter, Query#group, Query#facet, Query#mlt if you were relying on this behavior just wrap the arguments you passed to those methods into the solr.escapeSpecialChars(arg) method.

For example, for some weird reason you wanted to escape the special char *, don't ask me ;)